🔍 Key Concepts

• Net Positive Suction Head (NPSH) and what it physically represents in a pump system • Difference between total suction head, discharge head, and pump head • Role of vapor pressure in causing cavitation at the pump suction

💭 Think About

• When you subtract vapor pressure from the pressure at the pump suction, what are you trying to find in terms of how close the liquid is to boiling/cavitating? • Which term (from the choices) is specifically defined using the difference between suction pressure and vapor pressure rather than just the absolute suction or discharge conditions? • Think about which option is directly tied to cavitation margin at the pump inlet, not the total energy the pump adds to the fluid.

✅ Before You Answer

• Confirm which term is defined as suction pressure (expressed as head) minus vapor pressure (expressed as head). • Check that the term you choose is the one most directly related to avoiding cavitation at the pump suction. • Make sure you are not picking a more general term like pump head or discharge head, which do not explicitly involve subtracting vapor pressure.